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module Fig.Utils.FFI where
import Fig.Prelude
import Foreign.Ptr (Ptr, nullPtr)
import Foreign.Storable (Storable(..))
import Foreign.C.String
import Foreign.Marshal.Alloc
foreign import ccall "check_answer" c_check_answer :: Ptr CString -> CString -> CString -> IO Int
checkAnswer :: MonadIO m => Text -> Text -> m (Either Text Bool)
checkAnswer tcode tanswer = liftIO $
withCString (unpack tcode) $ \code ->
withCString (unpack tanswer) $ \answer ->
alloca $ \rerr -> do
res <- c_check_answer rerr code answer
err <- peek rerr
if err == nullPtr
then pure . Right $ res /= 0
else do
msg <- peekCString err
pure . Left $ pack msg
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